Mechanical characterization of bone graft substitute ceramic cements.

The aim of this laboratory work was to study the compressive and flexural characteristics of various commercially available bone graft substitute (BGS) ceramic cements, in their initial as-mixed condition, and compare them to polymethylmethacrylate (PMMA). The tested biomaterials were two different calcium phosphate cements, two different calcium sulphate cements, one nanocrystalline hydroxyapatite and one PMMA cement. All biomaterials were prepared according to manufacturers instructions and the methodology described in ISO 5833 (2002) for acrylic bone cement was followed, as the one closest approaching in vivo requirements. All BGS cements had a brittle behaviour and when subjected to mechanical stress they all failed under sudden crack propagations in their bulk. Both in compression and bending, all BGS cements failed under loads lower than those of PMMA. In compression, the calcium sulphate extra strength cement showed a strength value of approximately 60% of PMMA, the other cements following at a distance. In bending, all BGS cements showed strengths below 22% of PMMA. However, due to limited number and fragility of specimens, calculated bending strengths can only be considered as indicative figures with limited comparative value. The results of this in vitro study showed a varying mechanical performance between tested BGS ceramic cements, whilst all of them exhibited lower compression and bending strength than the selected PMMA. These findings, of course, cannot be directly extrapolated to surgical or clinical implications, since the adopted in vitro context does not necessarily reflect the actual in vivo conditions met by such biomaterials.

Complete avulsion of the extensor mechanism of a finger with simultaneous dislocation of the proximal interphalangeal joint.

We report a rare case of open dislocation of the proximal interphalangeal (PIP) joint, associated with simultaneous avulsion of the central band and distal insertion of the extensor mechanism, rapture of the proximal volar plate, and rapture of the ulnar collateral ligament of the PIP joint.Although isolated IP joint injuries are common, they rarely occur simultaneously in a single finger. Even more rarely are they accompanied by a complete avulsion of the extensor mechanism. Operative restoration of the injured structures is a necessity in order to achieve a good functional outcome.An initial forceful flexion of the finger resulting to rapture of the extensor apparatus and then followed by finger hyperextension and PIP joint dislocation is our perception of the possible mechanism of this extremely rare injury.

Total Dislocation of the Talus without a Fracture. Open or Closed Treatment? Report of Two Cases and Review of the Literature.

Complete dislocation of the talus not accompanied by a fracture is a very rare injury. The injury is encountered as a closed one even more rarely. Reviewing the literature we found that proposed treatments for total talus dislocation varied from primary talectomy or arthodesis (to avoid complications) to closed reduction and an under knee cast. Most importantly, there was no agreement among authors about the method of reduction (open/closed). We report our experience with two cases of closed total talus dislocation not accompanied by a fracture, and review the literature to retrieve evidence on whether a closed or open treatment should be preferred for this type of injury.

Polymorphisms of the vitamin D receptor gene and stress fractures.

Our aim was to evaluate the association between VDR polymorphisms and calcaneal Stiffness Index (SI) with stress fractures in a case control study including male military personnel. Thirty- two patients with stress fractures were matched with 32 uninjured healthy volunteers (controls), by gender, age, height, body weight, and level of physical activity. The two groups were genotyped for the FokI, BsmI, ApaI, and TaqI polymorphisms of the VDR gene with PCR-RFLP method. In addition, calcaneal SI was measured by heel quantitative ultrasound in both groups. Data were analyzed by chi-squared test and logistic regression analysis. The f allele was significantly more frequent in patients than in controls (p=0.013), while the B allele showed such a tendency without reaching statistical significance (p=0.052). Among the entire cohort, a 2.7-fold and a 2.0-fold increase in risk of stress fractures was associated with the f and B alleles (OR, 2.7, 95% CI, 1.2-5.9; p=0.014 and OR, 2.0, 95% CI, 1.0-4.1; p=0.053, respectively). No statistically significant association was found between the incidence of stress fractures and t or a alleles. Decreased T-scores were also associated with the presence of f and B alleles. Mean values of T-scores of SI were statistically significantly lower in patients than in controls (p=0.018). These results suggest that the FokI and BsmI polymorphisms of the VDR gene could be associated with increased risk of stress fractures among military personnel. Moreover, a low calcaneal SI could represent a measurable index of this increased risk.

Bilateral transient bone marrow edema or transient osteoporosis of the knee in pregnancy.

Transient osteoporosis or transient bone marrow edema is an uncommon self-limiting condition of unknown etiology. The most commonly affected joint is the hip, followed by the knee, ankle, and the foot. Simultaneous involvement of both hips has been reported exclusively in pregnant women. Bilateral knee involvement during pregnancy seems to be extremely rare. We present a case of bilateral transient bone marrow knee edema during pregnancy with complete resolution of symptoms and radiological findings after 10 months.

Simultaneous dislocation of the radial head and distal radio-ulnar joint. A case report.

Isolated dislocation of the distal radio-ulnar joint and isolated dislocation of the radial head in adults are not common injuries. A simultaneous dislocation of the radial head and distal radio-ulnar joint with no other injury seems to be extremely rare since only one report was found in the English literature. A similar case, but with some differences in presentation and treatment is reported.

Maggot infestation (myiasis) of external fixation pin sites in diabetic patients.

Diabetic patients, and especially elderly patients in a low-nutritional or immunocompromised state, are prone to a variety of opportunistic infections. 'Myiasis' is a term that refers to non-iatrogenic infestation of tissues by larvae, commonly known as maggots, of dipterous flies. Myiasis as a complication of fracture treatment by means of external fixation of long bones has not been reported. We present three diabetic patients, who suffered maggot infestation of their external fixation pin holes, and their outcome. Diabetes, immobilization, poor hygiene and low immune status are predisposing factors for developing myiasis, an extremely rare complication for external fixation of fractures.

Stress fractures in military men and bone quality related factors.

The aetiology of stress fractures is multifactorial, and many risk factors have been implicated. The aim of this study was to explore the relationship between stress fractures, factors and biochemical markers related to bone metabolism, and calcaneal stiffness index measured by quantitative ultrasound in a case control study including male military personnel beyond basic training. Thirty-two male patients with stress fractures were matched with 32 uninjured-healthy volunteers by age, height, body weight and level of physical performance. A questionnaire concerning the calcium intake, alcohol consumption and smoking was completed, the values of several biochemical markers were measured from blood samples, and calcaneal quantitative ultrasound was measured by heel ultrasound for all participants. Statistically significant higher levels of albumin (4.59 +/- 0.28 vs. 4.40 +/- 0.25, p = 0.006) and lower levels of serum osteocalcin (6.26 +/- 1.74 vs. 7.40 +/- 1.80, p = 0.012), mean values of T-scores (- 0.21 +/- 0.95 vs. 0.33 +/- 0.82, p = 0.018) and Z-scores (- 0.14 +/- 0.81 vs. 0.33 +/- 0.71, p = 0.016) were found among patients compared to controls. Based on the results, it seems that a decreased bone turnover and a low calcaneal stiffness index may be related to the incidence of stress fractures amongst male military personnel.

Post-operative pain after knee arthroscopy and related factors.

The aim of this study was to explore the intensity of post-arthroscopy knee pain during the first 24 hours, and to study the influence of pre-operative pain, tourniquet time and amount of surgical trauma on post-arthroscopy pain. In 78 male patients that underwent elective arthroscopic menisectomy or diagnostic arthroscopy of the knee, preoperative and post-operative pain were registered using the Visual Analogue Scale. Variance for repeated measures and for independent observations was analysed. Supplementary analgesia was required for 23% of the patients, more often in the recovery room and between 2 and 8 hours postoperatively. Of all factors analyzed, only time was statistically significant in determining the level of post-operative pain. Supplementary analgesia was required only in patients that underwent operative arthroscopy, and more often in patients with tourniquet time of more than 40 minutes. In conclusions, post-operative time is the most significant factor related to the post-arthroscopy knee pain.

Multifocal infection after hip fracture fixation: a case report.

We present the case of a seventy five year old female diabetic patient, who sustained an inter-trochanteric fracture of her left hip and was treated by dynamic hip screw fixation on the same day. The patient developed multifocal infection with three different and unusual types of bacteria isolated in blood and wound cultures. In spite of aggressive and repeated wound debridement, infection and blood sugar levels were impossible to control until metal removal, which led to fracture malunion. The patient denied further hip reconstruction surgery and ended up mobilizing with a walker and a limp.Multifocal infection is possible even after a routine Orthopaedic procedure on a patient with precipitating factors no more than diabetes mellitus. It is important to be aware of the possibility of simultaneous wound infection and septicemia by different agents.

Intramuscular haemangioma of the extensor pollicis brevis muscle with periosteal reaction of the radius: a case report and review of the literature.

We report the rare case of a histologically proven mixed-type intramuscular haemangioma, adjacent to the periosteum of the radius, that caused a periosteal reaction. We also carried out a review of the literature relevant to this case. A 28-year-old male professional drummer presented with an 8-month history of pain and swelling of the dorsal aspect of the right radius. Diagnosis was established on the basis of plain radiographs and magnetic resonance imaging, and was confirmed by histology. The lesion was treated solely by resection of the soft-tissue mass. The patient remained asymptomatic 4 years post-operatively, with no radiographic signs of recurrence. From a review of the literature, it is evident that the terminology for haemangiomas causing regional bone changes is unclear. A new classification of the intramuscular haemangiomas is proposed in order to distinguish between lesions that, according to current knowledge, exhibit radiological and clinical areas of overlap.

Are two screws enough for fixation of femoral neck fractures? A case series and review of the literature.

There is still a controversy in literature regarding the treatment of subcapital fractures of the hip with internal fixation. Different methods have been tested and studies such as in cadavers mainly prejudge the three cannulated screws application. We present a series of 20 patients in which percutaneous fixation with two parallel cannulated screws under specific technical conditions has led to an uneventful fracture union. No complications were observed at a one year follow-up. Reviewing the literature we found no previous clinical studies on the subject.

Ulnar nerve dislocation at the elbow: review of the literature and report of three cases.

Ulnar nerve instability without compression at the cubital tunnel is not common and even more rare is a dislocating nerve. We review the literature regarding the etiology of instability, its incidence and treatment. Snapping around the medial humeral epicondyle can also be caused by a subluxing medial head of the triceps. This pathology may be accompanied by symptoms from the ulnar nerve. Differential diagnosis even intraoperatively is therefore essential if effective treatment is to be given. We also present our own experience on the subject consisting of three cases, one of them with bilateral instability. In only one case there were clinical findings suggesting nerve compression. All laboratory and screening tests were normal, except for the nerve conduction studies in this one case. The main symptom was strong pain, especially during manual activities. Only two of the four subluxing nerves required surgical treatment which in our case was by anterior submuscular or subcutaneous transposition of the ulnar nerve. As diagnosis is not always easy and is usually made on clinical grounds, we also present a clinical test that we believe to be diagnostic for the situation.

Meniscal bucket handle tears: a retrospective study of arthroscopy and the relation to MRI.

In this study, we aim to evaluate the arthroscopic findings of meniscal bucket handle tears and to correlate them with the proposed MR imaging signs of meniscal bucket handle tears suggested in the literature. Thirty-six patients who had a diagnosis of bucket handle tear in arthroscopy, in either medial or lateral meniscus, were included in our study (32 males and 4 females). Meniscal tears were evaluated in arthroscopy according to Dandy's classification. The MRIs were retrospectively analyzed regarding the following findings: absence of bow tie sign, presence of double posterior cruciate ligament (PCL) sign, double anterior horn sign, flipped meniscus sign, disproportional posterior horn sign, and fragment within the intercondylar region. Locked types I and II fragment of medial meniscus and half-length, whole-width and whole length-half-width fragment of lateral meniscus in arthroscopy were basically correlated with fragment within the intercondylar notch and absent bow tie signs in MRI. We did not find the double PCL sign in any of the patients with a lateral meniscal bucket handle tear. The most common signs in MR images of meniscal bucket handle tears were the fragment in the notch sign and the absent bow tie sign. They were observed with equal frequency of 88.8%. The presence of double PCL sign, double anterior horn sign, flipped meniscus sign, disproportional posterior horn sign were less common (41.66, 33, 25, and 27.7%, respectively). We conclude that the presence of at least two of the six MRI signs should be regarded as highly suggestive for bucket handle tears of menisci.

Primary hydatid disease in femoral muscles.

Usually, intramuscular hydatid cysts are secondary, resulting from the spread cysts from other areas either spontaneously or after operations for hydatidosis in other regions. We present an unusual case of a primary hydatid cyst found in the left thigh of a 35-year-old woman, presenting as an enlarging soft-tissue tumour. Ultrasound, computed tomography and magnetic resonance imaging examinations revealed a multilocular intramuscular cyst in the anterior aspect of her left thigh, and no disease at any other location. We removed the entire cyst surgically, and macroscopic and microscopic histopathological examinations confirmed the diagnosis of muscular hydatidosis. Three years after the operation there had been no recurrence. In regions where hydatidosis is endemic, a tumour in any part of the body should be considered a hydatid cyst until proven otherwise.

Fractures of the proximal part of the femur in patients under 50 years of age.

We present a retrospective study of the epidemiology and the results of treatment of fractures of the proximal femur in 74 patients aged 50 or under. Cervical fractures comprised 17% of the 74 fractures and were equally caused by high and low energy trauma. Trochanteric and subtrochanteric fractures comprised 83% of the total and were mainly caused by high-energy trauma. The rate of complications was 25% for the cervical fractures (two avascular necroses and one non-union) and was attributed to a valgus malalignment and to the use of bulky implants. Similarly the rate of complications was 22.5% for the trochanteric and subtrochanteric fractures (mal-union and displacement into varus) and was attributed to early collapse of the fracture and the inability of the implant to withstand the strain before osseous union. Furthermore, intramedullary fixation of subtrochanteric fractures should be preferred to the sliding screw and side plate. In conclusion, we believe that proximal femoral fractures in young patients require great attention to the correct reduction and the appropriate choice of implant, in order to minimize the chances of the development of serious complications.

Nonunion of tibial fractures treated with external fixation. Contributing factors studied in 71 fractures.

We analyzed factors of importance for nonunion in a series of 39 closed and 32 open fractures of the tibia which were treated with external fixation. Factors analyzed included, age and sex of the patients, the mechanism of injury, the amount of soft tissue damage, the grade of comminution, the level at which the tibia was fractured, the presence of an intact fibula, the presence of multiple injuries, the type of external fixation used (Orthofix, STAR-90 or Hoffmann) and the need to supplement the stability of the reduction. We found that the type of open fracture, comminution of the fracture, extension the original wound for satisfactory reduction and fracture of the ipsilateral fibula, played a role in the development of nonunion.